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Not firing on all 8 thoughts

This is a discussion on Not firing on all 8 thoughts within the General Help forums, part of the LSx Technical Help Section category; We have a car that is a friend of mines that is giving us some fits that I could use ...

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    Not firing on all 8 thoughts

    We have a car that is a friend of mines that is giving us some fits that I could use some fresh thoughts on. Car is an 2002 SS that we installed a mild cam and long tubes as well as new clutch,slave and master. Had the car on the dyno and everything went fine untill he was driving home and noticed a ticking noise. We found a bent pushrod. So we pulled the head off and vacuum checked(it was fine) and resurfaced. I bled down the lifters and put the car back together and now feels like only running on 4 cyl, but no codes. Keep in mind that is not likely a mechanical timing issue as car ran great on dyno and that was not changed. It is getting fuel so is very much spark related. I pulled some of the plugs out to see what they looked like and they were not fouled or burnt up (new plugs as well). I am leaning towards a coil pack or two possibly but it is very strange that there were no issues at all spark related untill after head came off and I am thinking I missed something. Any thoughts are greatly appreciated.

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    Former Mopar Man 2002ssslp's Avatar
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    Did you make positive connection with the plug wire and the coil/plug. Recheck the connections, the ticking noise is from spark arch.

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    It is not ticking anymore, that was the bent pushrod. And I have checked the wire's but it can't hurt to check again. I would much rather that be the issue than the coil packs.

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    Checked all the plug wires again and they were all double clicked with no improvment. Going to start checking coil packs to make sure they are firing and if all is good, I quess nothing to do but change plugs again. If anyone else has any thoughts feel free to chime in. Thanks.

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    Drop&Drag matt evans's Avatar
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    crankshaft position sensor going bad maybe. coils on these cars rarely go bad.

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    Senior Member cpop98ws6's Avatar
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    Check you injectors. Make sure they are all plugged in and firing.

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    If you don't find any electrical gremlins a compression test might be a good idea. It's possible you have valves hanging open and it is bleeding off compression.

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    I have checked the injector pigtails, but not used a noid light test so I can check that. I will also watch the ckp to make sure it is sending signal. I will also do a compression test as I have not done that recently. The head as I stated checked out good on a vacuum test so if it is compression it would be lifter or pushrod related, and I bled down the lifters on the head I took off so not sure. But thanks for the ideas guys. Like I said, sometimes you get a little frustrated and need to be reminded of the little test to get you going back in the right direction. Thanks again.

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    All sensors working properly but lifters are pumping up and hanging the valves open. Only on the one head is there any issue but I am re-checking pushrod length anyway... IF they were too long though I would think the issue should be on both heads.

    Edit: had a thought. If the pushrods he got were boderline too long in the first place, then we milled that head to get it flat again (.010 off) that might be just enough to hang the valve open
    Last edited by texas97z; 12-05-2011 at 07:01 AM.

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    Spaz is My Mentor SMWS6TA's Avatar
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    Yes...that is why it is important to recheck push rod length after every milling heads.

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    Senior Member JayTA98's Avatar
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    Do you have the heat shield on the plug wires? are the plug wires new?

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    It was the pushrods. I checked the length and factory would have been the right length in this case. Put a factory set in last night and got 175 psi on all cylinders and she fired right up and runs good. doesn't want to go into reverse and clutch is engaging all the way at floor (all brand new clutch and fluid parts) so going to try bleeding it again, but the main issue is solved. Thanks for the thoughts everyone.

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    Glad ya got it figured out. We had to bleed a friends ws6 a few times before it was just right.

  14. #14
    Spaz is My Mentor SMWS6TA's Avatar
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    Glad you fixed it and good luck bleeding that clutch. A mitty vac will be the best method otherwise be prepared for it to take a while.


    Some go quick, some take forever.





    Crap I just remember that I have my plugs do. I've had them for over a month now, just not excited to put them in. Been waiting for something else to do with it.
    Last edited by SMWS6TA; 12-16-2011 at 09:59 PM.

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